Air cleaner



Patented May 1930 y UNITED STATES PATENT ori-ICE CHARLES L. MCCUEN,'OF LANSING, MICHIGAN, ASSIGNOR T0 GENERAL MOTORS COR- PORATION, 0F DETROIT, MICHIGAN, A CORPORATION OF DELAWARE AIR CLEANER Application xled July 18,

This invention relates to a Ventilating system for automobile crankcases and particularly to a system of the type in which a portion of the carburetor air supply is taken from the crankcase. It is desirable that the air supplied to the carburetor from the atmosphere be relieved of its dust content by passage through an air cleaner. It is not necessary to clean the vapors drawn from the crankcase for the are relatively free fromA dust, since the on y communication between the crankcase and the atmosphere is through a breather opening which is normally protected by a suitable cowl, screen or a separate air cleaner. To secure effective ventilation it is desirable that substantially the full intake suction be applied to thev crankcase. I have devised a convenient and simple arrangement whereby the carburetor is insured a supply of clean air without materially reducing the suction applied to the crankcase. The arrangement consists n providing a connection between the engine crankcase and the air cleaner at a point where dust separation has been substantially completed. In the case of a centrifugal cleaner, connection is made with the enter of the vortex preferably in line with yhe outlet conducting clean air from the vortex to the engine intake. By thus'locatlng lche crankcase connection I am assured of a maximum degree of suction for the vacuum at this point in the cleaner is very high.'

As the crankcase vapors contain a considerable amount of oil I have preferred to make the connection with the crankcase through the Vvalve chamber so that much of the oil will be caught by impingment on the valve mechanism and the walls of the chamber and will not be drawn into the carburetor. I

I have also so designed the assembly that the single bolt or stud usually employed to hold the valve cover in place may, by slight modification, be employed to hold the ventilating connection in place.

In the drawing:

Figure 1 is a vertical section through an internal combustion engine to which my ventilating system is applied.

1928. Serial No. 293,644.

Figure 2 is a side elevation of the arrangement of Figure' 1.

Figure 3 is a section on line 3--3 of Figure 2.

On the drawing, 10 indicates an internal combustion engine having a crankcase 12 provided with the conventional breather 14 for admitting air'to the crankcase. The breather is illustrated as equipped with a screen 16 for lntercepting dust. To the breather cap is secured a rod 18 which may be used to indicate the level of oil in the crankcase. At 20 I have shown the usual carburetor'supplying the engine with fuel and equipped with an a1r intake 22 upon which is mounted an air cleaner 24. The cleaner comprises a cylindrical casing 26 provided at 28 with an annular se.ries of helical blades for imparting a wh1rl1ng motion to the entering air. At the other end of the casing the cleaner is provided with a dust discharge slot 30. 32 represents the clean air outlet which is equipped with the air straightener 33. In this type of cleaner it is obvious that the helical blades cause the air to whirl, segregating the dust in the outer layers and eventually effecting its discharge through the slot 30. The clean air then reverses its direction and passes outwardly through the outlet 32. The air straightener takes the whirling motion out of the air as it enters the carburetor. p

34 indicates the valve chamber housing parts of the valve mechanism such as the usual valve stems, springs and tappets. These chambers are in communication with :the crankcase through dpassages 36. The valve chambers are rovi ed with covers 38. Conduit 40 estab 'shes communication between one of the valve chambers and the center of the casing 26 of the cleaner. The conduit is preferably S-shaped, as shown, and from the engine wall extends stud 41 passing through the aperture in the valve cover and through the conduit 40. A nut 44 is engaged on the stud for clamping the conduit and cover to the engine block. L

With this arrangement it is apparent that the air drawn out of the crankcase is re laced by fresh air through the breather 14. rankcase vapors find admission to the air cleaner at the center of the vortex where the suction a\cover for the valve c is hi l1 sothat circulation of air through the crankcase is promoted.' By drawing the crankcase vapors through the valve chamber the particles of oil carried thereby are caused to impinge upon the valve mechanism and the wallsoi` the chamber so that the vapors passing to the carburetor are relatively free of oil. If desired, special means such as bales may be provided in the conduit 40 leading crankcase va Ors to the cleaner for the purpose of more e ectively separating the oil particles therefrom. However, I prefer to make use of the valve chamber for thls purpose.

I claim:

1. An internal combustion engine having a crankcase having an air inlet, a suction operated air intake, an air cleaner for the intake, lsaid cleaner including means for whirl-kv ing the air and an outlet for clean air leading from the center of the vortex, and a connection from the crankcase to the center of the vortex vforwithdrawing air from the crankcase and delivering it directly to the clean c CHARLES L. CCUEN.

air outletwithout undergoing cleaning action.

2. In the combination as defined in claim l, said engine having a valve chamber in communication with the crankcase and said connection leading from the -valve chamber so as to elect separation of oil particles from the vapors in their passa e through the chamber.

3. An internal com ustion engine having a crankcase provided with an air inlet, a suction operated air intake andan air cleaner for the intake provided with means for separating dust from the air and with an axial cleanA air outlet, and a conduit communicating with the crankcase and connected with the cleaner in alignment with the clean air outlet so that the vapors passing into the cleaner from` the crankcase discharge directly into the clean air outlet without undergoing cleaning action.

4. An internal combustion engine having a v crankcase provided with an air inlet, a valve with the crankcase, amber, a suction operated air intake, an air cleaner for the intake provided with means for separating dust from the air and with an axial clean air outchamber communicatinlg let, and a conduit mounted on the cover and connected to the cleaner in alignmentwith the clean air outlet so that the vapors passing into the cleaner from the crankcase discharge directly into the clean air outlet Without undergoing cleaning action.

5. An internal combustion engine'having a crankcase provided with an air inlet, a valve chamber communicating with the crankcase, a suction operated air intake, an air cleaner for the intake provided with means for separating dust from the entering air and with an axial clean air outletfand a conduit communicating with the valve chamber and con- 

